Windmills and wind turbines are well known in the art. Windmills traditionally include a plurality of blades or vanes connected to a rotatable shaft. Wind (or other fluids) act upon the blades to create an aerodynamic or hydrodynamic reaction upon the blades causing the shaft and blades to rotate about the axis of the shaft. Windmills have traditionally been employed across the world to perform functions from pumping of water, grinding grains and with respect to changing kinetic energy to electrical energy, being coupled to other devices for generating and transmitting electrical power. In recent times, due to rising energy costs and awareness of the need for alternative energy sources, interest has greatly increased in devices adapted to capture the power of the wind.
Examples of the prior art include U.S. Pat. No. 5,126,584 to Ouellet, U.S. Pat. No. 4,926,061 to Arreola and U.S. Pat. No. 4,047,834 to Magoveny et al. U.S. Pat. No. 5,126,584 illustrates a windmill including moveable vanes, the vanes being formed of an outer stationary shutter and an inner moveable shutter. U.S. Pat. No. 4,926,061 illustrates a wind trap energy system, each wind trap having a pair of vanes 60 degrees apart from the other for interception of wind kinetic energy from any direction. U.S. Pat. No. 4,047,834 to Mogaveny et al., discloses a windmill having fixed vanes on an outer perimeter of a fixed base member and a plurality of fixed buckets mounted to a rotor mounted on an axle.
While these references generally disclose windmills of the type contemplated by the present invention, these references do not teach the geometry of the curved, adjustable blades having a wing shaped configuration of the present invention.
Accordingly, there is a need for a relatively simple, inexpensive windmill with vertically oriented blades capable of being positioned at various angles.